Field of the Invention
The present invention relates to an image processing apparatus and an image processing method.
Description of the Related Art
In recent years, digital cameras capable of performing omnidirectional photographing around photographers to generate omnidirectional images have been rolled out. Omnidirectional images have entire celestial sphere shapes and are large in size. Therefore, in the reproduction of omnidirectional images, geometric conversion processing is generally applied to the omnidirectional images to display some regions (partial regions) of the omnidirectional images having undergone the geometric conversion processing (Japanese Patent Application Laid-open No. 2014-6880 and Japanese Patent Application Laid-open No. 2013-27021). Users can discriminate omnidirectional images by successively switching and displaying partial regions. With this method, however, users are required to confirm partial images, which are successively switched and displayed, for a long period of time to discriminate omnidirectional images, and they cannot easily discriminate the omnidirecitional images.
As an image display method that allows users to easily discriminate images, there has been known a method of displaying thumbnail images obtained by downsizing entire images. In omnidirectional images, however, objects are curved and directions (vertical and horizontal directions) of the object depends on positions inside the omnidirectional images. Therefore, users have difficulty understanding the contents of omnidirectional images and their thumbnail images and discriminating omnidirectional images from thumbnail images of the omnidirectional images.
Here, a method of displaying thumbnail images of omnidirectional images having undergone the geometric conversion processing is assumed. However, since omnidirectional images are large in size, objects in thumbnail images of the omnidirectional images are extremely finely displayed. Therefore, users also have difficulty understanding the contents of thumbnail images of omnidirectional images having undergone the geometric conversion processing and discriminating omnidirectional images from thumbnail images of the omnidirectional images having undergone the geometric conversion processing.
In technology disclosed in Japanese Patent Application Laid-open No. 2014-6880, thumbnail images in some regions of omnidirectional images are generated. However, since this technology requires a user's operation to select and specify regions for thumbnail images, users are not allowed to easily generate the thumbnail images.